[media] media-entity: protect object creation/removal using spin lock
Some parts of the media controller are using mutexes while
others are using spin locks in order to protect creation
and removal of elements in the graph. That's wrong!
Also, the V4L2 core can remove graph elements on non-interactive
context:
BUG: sleeping function called from invalid context at include/linux/sched.h:2776
Fix it by always using spin locks for graph element addition/removal,
just like entity creation/removal is protected at media-device.c
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
index ee0f813..b1390d8 100644
--- a/drivers/media/media-entity.c
+++ b/drivers/media/media-entity.c
@@ -700,9 +700,9 @@
if (entity->graph_obj.mdev == NULL)
return;
- mutex_lock(&entity->graph_obj.mdev->graph_mutex);
+ spin_lock(&entity->graph_obj.mdev->lock);
__media_entity_remove_links(entity);
- mutex_unlock(&entity->graph_obj.mdev->graph_mutex);
+ spin_unlock(&entity->graph_obj.mdev->lock);
}
EXPORT_SYMBOL_GPL(media_entity_remove_links);
@@ -792,9 +792,9 @@
{
int ret;
- mutex_lock(&link->source->entity->graph_obj.mdev->graph_mutex);
+ spin_lock(&link->source->entity->graph_obj.mdev->lock);
ret = __media_entity_setup_link(link, flags);
- mutex_unlock(&link->source->entity->graph_obj.mdev->graph_mutex);
+ spin_unlock(&link->source->entity->graph_obj.mdev->lock);
return ret;
}
@@ -932,9 +932,9 @@
void media_remove_intf_link(struct media_link *link)
{
- mutex_lock(&link->graph_obj.mdev->graph_mutex);
+ spin_lock(&link->graph_obj.mdev->lock);
__media_remove_intf_link(link);
- mutex_unlock(&link->graph_obj.mdev->graph_mutex);
+ spin_unlock(&link->graph_obj.mdev->lock);
}
EXPORT_SYMBOL_GPL(media_remove_intf_link);
@@ -954,8 +954,8 @@
if (intf->graph_obj.mdev == NULL)
return;
- mutex_lock(&intf->graph_obj.mdev->graph_mutex);
+ spin_lock(&intf->graph_obj.mdev->lock);
__media_remove_intf_links(intf);
- mutex_unlock(&intf->graph_obj.mdev->graph_mutex);
+ spin_unlock(&intf->graph_obj.mdev->lock);
}
EXPORT_SYMBOL_GPL(media_remove_intf_links);